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Weight Loss Regime of an Eared Grebe

Dear Jane,

I laughed so hard at your account of the Pied-bill Grebe’s high standards of cleanliness! This blogging adventure continues to toss up one surprise after another.

I took advantage of a beautiful Saturday morning last week to set off to see what I could see. Twenty species and almost three hours later I dragged my old bones home after at least one big surprise. The best treat of the morning was my first EARED GREBE of the season, a migrating cousin of the year-round Pied-billed Grebe. Her modest grey and white presence is utterly unremarkable, although I love her little powder puff tail!

Scrawny Eared Grebe, first of season, October 1, 2016, between Laurel and Riverside Bridges

I certainly had no idea about what she had just gone through until I got back home and looked her up in Birds of North America. I was astonished to read she had just  performed an annual miracle of bodily weight loss and gain that is the most extreme of any known bird in the world. Apparently, when she arrived at her breeding grounds last spring (as close as Nevada or as far as southern Canada), she began an unparalleled eating binge that more than doubled her arrival weight! During this period her chest muscles atrophied to the point that she was no longer able to fly! Then, just before her fall departure for Santa Cruz, her body began to rapidly metabolize all the fat she had acquired during the breeding months in order to make it possible to fly here to Santa Cruz!

Filled-out Eared Grebe Winter/Spring 2015 San Lorenzo River

Even the size of her heart and digestive organs decreased significantly. Can you believe that she lost up to 75% of all her added weight!  Now that she is back, she will start the process all over again for the winter months – binging all fall and winter, then fasting just before she returns to her breeding grounds.  The consequence of this extreme fluctuation in weight is that the Eared Grebe cannot fly for 9 to 10 months a year! Weight Watchers take note!

Anyway, while I was watching this newly arrived little grebe busily diving for fish (and still ignorant of  how extremely hungry she must be!) I noticed that two of the Leveelies were descending the east slope of the levee, across the river from me, with their eyes on a beach ball caught in some brush along the river. (I had earlier seen them haul a huge blue blanket out of the water, another impressive feat.)  They were quite close to the grebe and I was worried that they might inadvertently disturb this busily fishing little soul.

Unidentified Leveelie with trash pail and eye on beach ball.


Eared Grebe in lower right hand corner

I recognized my friend Sharon De Jong, one of the Leveelies, and yelled out ‘Sharon!’ She waved. I hoped she would be able to hear me. I pointed to the grebe and yelled as loud as I could, “That’s an Eared Grebe, just arrived.” She consulted with her companion, they waved, and immediately turned around and went back up the levee slope, leaving the grebe to its hungry search.

Later I ran into all of the Leveelies congregated on the west bank after a long morning of gathering trash. Even Scott Collins, the assistant City Manager, stopped by with his son and a bucket to help pick up trash. R. Leveelies Julie Morley, two unidentified, Sharon DeJong and Scott Collins

I talked to Janet Fardette, the leader of the group. I told her how good it was to see her back on the river after her announcement that the group would stop its years and years of volunteer clean-up work on the river. I asked her about her decision to leave and about why they had decided to come back. She said, “We left because of the criminal behavior, and especially the murder, which happened right where we clean up. Some of the Leveelies were saying they couldn’t do it anymore.”   When I asked her why she came back, she said, “Because the City has done its job!” Before she could elaborate, she was off talking to one of the many volunteers. I gave Sharon a hug and thanked her for giving up on the beach ball. She had just arrived back from a vacation in Hawaii the night before. I expressed admiration that she was out on the River the very next day in her waders to pick up trash. “I didn’t want to miss it!” she said. Thanks, Janet and Sharon and all the other dedicated volunteers who help keep the river clean and safe.   And thanks to the City who is now working harder to protect the home of birds and other wild creatures. As Julie Morley, another Leveelie, said to me, “This should be a protected wildlife area with fences and signs.” I couldn’t have agreed with her more!!

I also saw two other first-of-season birds, the YELLOW-RUMPED WARBLER and a  COMMON GOLDENEYE, although the latter may be the one that overwintered. This is pretty early for a returning Goldeneye.

FOS female Common Goldeneye, or overwintering bird?  October 1,2016, between Soquel and Laurel St. Bridges


Again, here is my eBird list for those of you who might like to know all the birds that I saw during my three-hour walk last Saturday.

Thank you, River, for all the treasures you conceal and reveal.

Fall greetings to you, Jane! I know you also have your eye out for your returning friends down there on the estuary.  It’s an exciting time of year.











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